Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: Azzkikrcuda]
#1978057
12/28/15 07:38 PM
12/28/15 07:38 PM
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Joined: Jan 2003
Posts: 1,814 North Dakota
Azzkikrcuda
OP
top fuel
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OP
top fuel
Joined: Jan 2003
Posts: 1,814
North Dakota
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From the pics it looks nice, Pendulum counter weights, Drilled thru the Mains, Scalloped bolt flange. Just missing knife edged counter weights.
The only Carbs I care about are under the hood!
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: Azzkikrcuda]
#1978067
12/28/15 07:50 PM
12/28/15 07:50 PM
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Joined: May 2004
Posts: 12,478 Taxes & Virus's R-US, NY
Dragula
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I Live Here
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Thanks for posting that.....I have a 400 block I was thinking of doing a low deck 512 for next year with....Not sure how much faster I really want to go though....My pump gas RB 512 has already been 6.13 in the 1/8th....And I am not sure what the safety requirements are for going faster.
Last edited by Dragula; 12/28/15 07:51 PM.
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: AndyF]
#1978076
12/28/15 08:02 PM
12/28/15 08:02 PM
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Joined: Jan 2003
Posts: 4,395 The Pale Blue Dot
Skeptic
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master
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The Pale Blue Dot
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I hadn't seen that before but I like the idea. I used a SCAT superlight crankshaft in my last 470 build. I really like the idea of taking unnecessary weight off the crankshaft if you can afford it. Was that a special order? They only show the RB mains and no 3.91" strokes on the website. Thanks, Steve
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: rebel]
#1978079
12/28/15 08:10 PM
12/28/15 08:10 PM
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Joined: Jun 2003
Posts: 52,972 Romeo MI
MR_P_BODY
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Romeo MI
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i just got my std 400/512 Source crank back from being balanced. the machinist said he only had to take 40grams off the crank to match my rods n pistons. how do you go with a crank thats 3000 grams less to start with? Just depends on WHERE the weight is and where it isnt.. I normally turn down the counter weight a considerable amount so they spin quicker.. along with a sharper edge on the leading edge.. I've want to do the same edge on the trailing side to reduce windage
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: MR_P_BODY]
#1978128
12/28/15 09:14 PM
12/28/15 09:14 PM
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Joined: Jan 2003
Posts: 31,203 Oregon
AndyF
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Oregon
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Andy... that Scat crank looks pretty nice..what did it take to balance in on your set up Well the crank came balanced for the stroker kit but the pistons ended up being lighter than advertised so we had to re-balance the crank. It took a little work to do the re-balance. Had the crank come un-balanced the job would've been easier. Final bobweight on this crank was 2222 grams so it is fairly light for a big block.
Last edited by AndyF; 12/28/15 09:24 PM.
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: Skeptic]
#1978136
12/28/15 09:20 PM
12/28/15 09:20 PM
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Joined: Jan 2003
Posts: 31,203 Oregon
AndyF
I Win
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I hadn't seen that before but I like the idea. I used a SCAT superlight crankshaft in my last 470 build. I really like the idea of taking unnecessary weight off the crankshaft if you can afford it. Was that a special order? They only show the RB mains and no 3.91" strokes on the website. Thanks, Steve Kind of a semi-custom order. SCAT has raw forgings on hand and they can machine up most anything. They make a lot of NHRA Super Stock cranks with Honda journals and stuff like that that isn't in the catalog. You just have to tell them what you want and wait a few weeks for it to show up. SCAT has the CAD files on hand to produce fully machined lightweight Mopar cranks but they don't really advertise it. You just have to call them and talk it over with the engineer. The nice thing about working with SCAT is they have the ability to do all of the machine work and heat treating and finish work in the USA. Some of the other crank vendors are just box movers. So if it isn't in the catalog they can't make it. SCAT imports raw forgings and then does the rest on shore so they can move things around if you want.
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: AndyF]
#1978155
12/28/15 09:50 PM
12/28/15 09:50 PM
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Joined: Jan 2003
Posts: 4,395 The Pale Blue Dot
Skeptic
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The Pale Blue Dot
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Kind of a semi-custom order. SCAT has raw forgings on hand and they can machine up most anything. They make a lot of NHRA Super Stock cranks with Honda journals and stuff like that that isn't in the catalog. You just have to tell them what you want and wait a few weeks for it to show up.
SCAT has the CAD files on hand to produce fully machined lightweight Mopar cranks but they don't really advertise it. You just have to call them and talk it over with the engineer.
The nice thing about working with SCAT is they have the ability to do all of the machine work and heat treating and finish work in the USA. Some of the other crank vendors are just box movers. So if it isn't in the catalog they can't make it. SCAT imports raw forgings and then does the rest on shore so they can move things around if you want.
Nice! Thanks for the info. So....How much $$$?
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: Azzkikrcuda]
#1978186
12/28/15 10:50 PM
12/28/15 10:50 PM
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Joined: Apr 2005
Posts: 1,509 TN
SCATPACK 1
pro stock
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pro stock
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Posts: 1,509
TN
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440 source offered the lightened cranks about 10 or so years ago. Remember they blew them out at a really low price to get rid of them. Not sure if it was an issue with the cranks or just no demand. I wanted one at that time but they were sold out when I finally placed my order. But we ran their regular crank for many years with zero issues in a drag only motor. Good luck with it.
Old Geezer Racing
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: Azzkikrcuda]
#1978220
12/28/15 11:26 PM
12/28/15 11:26 PM
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Joined: Jan 2005
Posts: 12,478 Kalispell Mt.
HotRodDave
I Live Here
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Kalispell Mt.
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Is pendulum cuting really worth anything or just good for advertising? Seems that as close to the centerline as that weight is they could remove smaller weight farther out and be just the same inertia to accelerate it? Seems like it would make the crank a tiny bit more flexible as well where turning down the outer diameter of the counter weight would remove unwanted stress.
I am not causing global warming, I am just trying to hold off a impending Ice Age!
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: SCATPACK 1]
#1983526
01/04/16 04:49 PM
01/04/16 04:49 PM
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Joined: Jun 2004
Posts: 744 Carson City, NV
440sourcedotcom
super stock
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super stock
Joined: Jun 2004
Posts: 744
Carson City, NV
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440 source offered the lightened cranks about 10 or so years ago. Remember they blew them out at a really low price to get rid of them. Not sure if it was an issue with the cranks or just no demand. I wanted one at that time but they were sold out when I finally placed my order. But we ran their regular crank for many years with zero issues in a drag only motor. Good luck with it. That is correct. We offered these lightweight crankshafts from 2006-2008, but discontinued them due to low demand. We never had any problems with them. Over the last year or two, we noticed that we had an increase in people asking for them again, so we decided to bring them back. Also, on the question about 3000 grams being taken off the crank, bobweight is being confused with total weight of the crankshaft. The 3000 grams is being removed from the total weight of the crankshaft (as if it was being weighed on a standard scale.) The bobweight, which is related to how the crankshaft is balanced, (essentially the "difference" between the crankpin side of the crank and the counterweight side, if you were to split the crank in "half") remains unchanged.
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: 440sourcedotcom]
#1983994
01/05/16 05:35 AM
01/05/16 05:35 AM
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Joined: Mar 2007
Posts: 3,298 West Coast, USA
jbc426
master
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master
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I have one of the lightened 440 Source stroker cranks in my 493". It's swinging a set of max-lightened & coated Ross forged flat tops in a zero-decked block and fed by a set of ported Indy EZ's and an aluminum Eddy sixpack intake. It's a high quench motor with those little heart shaped chambers on the Indys. The crank was beautiful.
The motor spins up almost instantly, and even with a McLeod steel flywheel and street twin clutch hanging on the back of it, it takes a little extra attention to pull away from a stop from an idle without all the normal inertia. I can feel the difference in reciprocating weight when I drive my buddies 440 manual trans car. I forget what the bob weight came out to.
It's got around 6000 something miles on it, and is still going strong. Hopefully it will live a long healthy life. The car it's in puts people right in shock on a regular basis.
Last edited by jbc426; 01/05/16 05:38 AM.
1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 4.10's 1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3800 stall lock-up converter and 4.30's (closest thing to an automatic 5 speed going)
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: AndyF]
#2454016
02/19/18 05:19 PM
02/19/18 05:19 PM
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Joined: Jul 2014
Posts: 68 USA MO
cdoublejj
member
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member
Joined: Jul 2014
Posts: 68
USA MO
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I hadn't seen that before but I like the idea. I used a SCAT superlight crankshaft in my last 470 build. I really like the idea of taking unnecessary weight off the crankshaft if you can afford it. Was that a special order? They only show the RB mains and no 3.91" strokes on the website. Thanks, Steve Kind of a semi-custom order. SCAT has raw forgings on hand and they can machine up most anything. They make a lot of NHRA Super Stock cranks with Honda journals and stuff like that that isn't in the catalog. You just have to tell them what you want and wait a few weeks for it to show up. SCAT has the CAD files on hand to produce fully machined lightweight Mopar cranks but they don't really advertise it. You just have to call them and talk it over with the engineer. The nice thing about working with SCAT is they have the ability to do all of the machine work and heat treating and finish work in the USA. Some of the other crank vendors are just box movers. So if it isn't in the catalog they can't make it. SCAT imports raw forgings and then does the rest on shore so they can move things around if you want. so are the SCAT cranks similar to 440 source cranks? I guess that means I could order a stock stroke super light by the sounds of it
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: 440sourcedotcom]
#2454019
02/19/18 05:26 PM
02/19/18 05:26 PM
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Joined: Jul 2014
Posts: 68 USA MO
cdoublejj
member
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member
Joined: Jul 2014
Posts: 68
USA MO
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440 source offered the lightened cranks about 10 or so years ago. Remember they blew them out at a really low price to get rid of them. Not sure if it was an issue with the cranks or just no demand. I wanted one at that time but they were sold out when I finally placed my order. But we ran their regular crank for many years with zero issues in a drag only motor. Good luck with it. That is correct. We offered these lightweight crankshafts from 2006-2008, but discontinued them due to low demand. We never had any problems with them. Over the last year or two, we noticed that we had an increase in people asking for them again, so we decided to bring them back. Also, on the question about 3000 grams being taken off the crank, bobweight is being confused with total weight of the crankshaft. The 3000 grams is being removed from the total weight of the crankshaft (as if it was being weighed on a standard scale.) The bobweight, which is related to how the crankshaft is balanced, (essentially the "difference" between the crankpin side of the crank and the counterweight side, if you were to split the crank in "half") remains unchanged. I'd like to be able to get a forged hardened super light stock stroke crank for the rb 440
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: cdoublejj]
#2454024
02/19/18 05:30 PM
02/19/18 05:30 PM
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Joined: Jan 2003
Posts: 19,544 Las Vegas
Al_Alguire
I Live Here
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I Live Here
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Call Scat they can make one.
"I am not ashamed to confess I am ignorant of what I do not know."
"It's never wrong to do the right thing"
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: Azzkikrcuda]
#2454025
02/19/18 05:30 PM
02/19/18 05:30 PM
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Joined: Jan 2003
Posts: 19,544 Las Vegas
Al_Alguire
I Live Here
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I Live Here
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Las Vegas
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Crower can do it as well. Don't have a picture of my Crower crank handy though
"I am not ashamed to confess I am ignorant of what I do not know."
"It's never wrong to do the right thing"
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: Azzkikrcuda]
#2454075
02/19/18 07:09 PM
02/19/18 07:09 PM
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Joined: Oct 2014
Posts: 104 Washington
weedburner
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Joined: Oct 2014
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Washington
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If your racing where the engine rpm varies very little, like a Powerglide equipped drag car with 800-1000 rpm drop on a single shift, there won't be much advantage to a liteweight crankshaft / rotating assy. If you are racing where the engine rpm varies a lot, like a 4spd manual drag car losing 2000rpm on each of 3 shifts, weight of the rotating assy can make a big difference.
Here's a comparison of two engines that I installed a street/strip manual 4spd car, only significant difference between them was different component weights. Not Mopar, but the results are still relevant...
...Engine #1 was 4.04" x 3.48" w/ 5.7" i-beam rods, hypers with gas ported spacers and 1.2mm rings (12lb oil), 49lb crank and heavy 8" balancer, 1863g bobweight.
...Engine #2 is 4.03" x 3.48" w/ 6" aluminum rods, forged pistons with lateral gas ports and 1.5mm rings (14lb oil), 42lb crank with pendulum style counterweights, drilled rod journals, 6" balancer, 1492g bobweight .
Both had flat tops with nearly identical quench and compression. Exact same intake and carb, same carb calibration. Exact same cam installed on the exact same intake centerline. Exact same flywheel and pressure plate installed in exactly the same car, same weight, with exactly the same gearing and tires. Even though these tests were a couple weeks shy of 2 years apart, both tests are on the same location with zero tire spin and conditions were very close to the same. The car itself was basically a time capsule...I lost engine #1 a few weeks after the test, and i had other irons in the fire so the car sat until engine #2 was ready to install...just picking up where i had left off with regard to developing the car. Here's the average rates that each engine gained rpm WOT thru the gears...
1st gear 2000 to 4000 rpm- engine #1 1634 rpm/sec........engine #2 1910 rpm/sec (276 rpm/sec difference) = 18.8% gain 1st gear 4000 to 6000 rpm- engine #1 1975 rpm/sec........engine #2 2217 rpm/sec (242 rpm/sec difference) = 12.2% gain 2nd gear 4000 to 6000 rpm- engine #1 1070 rpm/sec.......engine #2 1116 rpm/sec (46 rpm/sec difference) = 4.2% gain 3rd gear 4000 to 6000 rpm- engine #1 535 rpm/sec.........engine #2 541 rpm/sec (6 rpm/sec difference) = 1.1% gain No 4th gear data available for comparison.
As you can see, the quicker an engine sweeps thru a gear, the more you will gain from lightweight components. These two engines might both make around 500ft/lbs each running steady state NA, making engine #2's 12.2% gain in 1st gear from 4-6k roughly equal to around a 60hp advantage over engine #1.
Sometimes it helps to think about what happens in opposite extremes...
A given engine has a maximum acceleration rate that it can gain rpm without any external load at all...like a neutral free-rev. At that point all it's power is being used to accelerate itself, and no power is left over to do external work. The lighter an engine's rotating assembly, the easier/quicker it is to accelerate. Sweeping thru the heart of it's torque curve, engine #1 in my example above could gain rpm without a load at the average rate of 8500 rpm per second. Engine #2 could gain rpm without a load at the average rate of 11,515 rpm per second.
On the other end of the spectrum if a car accelerates and works it's way thru the gears, it eventually reaches a point where the engine can no longer accelerate the car. At that point all the engine's power is being used to overcome friction/drag, and there is no power left over for acceleration. This is also the point where the weight of the rotating assy no longer has any effect at all on the power output of the engine. All the torque the engine is making is reaching the transmission's input shaft, no power is being absorbed by the rotating assy as inertia. Operating WOT against maximum load, engine #1 and engine #2 both make the same power.
Looking at these two extremes makes it easier to understand how acceleration rate can have such a huge effect on dyno data. The two otherwise identical engines will make about the same torque when operating against maximum load at a constant rpm, but if engine #1 were dynoed at an acceleration rate of 8500 rpm per second, it would make zero torque on the dyno. Engine #2 still has power left over to move the needle.
If you are running wide open across the ocean, less crankshaft weight will probably hurt you more than help you. If you are a dirt track sprint car on the pole during a re-start, less crankshaft weight is going to be a “BFD”! Most of us here will fall somewhere in between.
Grant
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: Azzkikrcuda]
#2454411
02/20/18 04:25 AM
02/20/18 04:25 AM
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Joined: Aug 2003
Posts: 8,793 Mt.Gilead, Ohio
OhioMopar
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master
Joined: Aug 2003
Posts: 8,793
Mt.Gilead, Ohio
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I have an ultralight in my low deck 512. It's going in front of a 4-speed. It wraps up really quick on the test stand. I'll hopefully see how it does in the car this year.
1969 Dart GTS 340 1969 Coronet R/T X9 N-96 1999 Dodge Dakota R/T RC 2015 Dodge Dart GT 2019 Ram 2500 Big Horn
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: OhioMopar]
#2454436
02/20/18 08:52 AM
02/20/18 08:52 AM
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Joined: May 2004
Posts: 12,478 Taxes & Virus's R-US, NY
Dragula
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I Live Here
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Mine is done, and we have a few passes on it...Hits the convertor hard! I love the way it revs...We are expecting 9.60's out of my combo this year...
Last edited by Dragula; 02/20/18 08:53 AM.
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: Dragula]
#2454614
02/20/18 03:53 PM
02/20/18 03:53 PM
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Joined: Aug 2003
Posts: 43,744 Bend,OR USA
Cab_Burge
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I Win
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Posts: 43,744
Bend,OR USA
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Another thing to consider is total rotational weight on how it affects traction, stick shift car with small C.I. normally will use a heavier flywheel and clutch assembly than a larger motor will due to the difference in the ability of the car to spin the tires, like how a converter stall can affect traction Lightweight is right, big (C.I., carb, exhaust, tires) is best
Last edited by Cab_Burge; 02/20/18 03:54 PM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: AndyF]
#2455620
02/22/18 02:40 PM
02/22/18 02:40 PM
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Joined: Mar 2007
Posts: 3,298 West Coast, USA
jbc426
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Andy... that Scat crank looks pretty nice..what did it take to balance in on your set up Well the crank came balanced for the stroker kit but the pistons ended up being lighter than advertised so we had to re-balance the crank. It took a little work to do the re-balance. Had the crank come un-balanced the job would've been easier. Final bobweight on this crank was 2222 grams so it is fairly light for a big block. Andy, I choose one of 440 Source's Ultra-light cranks for my RB when they were first offered thinking the reduced weight of the reciprocating assembly would be easier on the stock block's mains. I don't have the bob weight handy, but the replacement pistons came in at 524 grams to match the old ones. I had the motor apart to change pistons to lower the compression 2 points and resolve some valve train harmonics issues that resulted from insufficient of spring pressure/ hydraulic rollers being spun to high. There was no sign of cap walk on the parting line or on the caps. How much do you suspect the lighter weight crank and reciprocating assembly actually helps the stock blocks live?
1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 4.10's 1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3800 stall lock-up converter and 4.30's (closest thing to an automatic 5 speed going)
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: jbc426]
#2455667
02/22/18 03:54 PM
02/22/18 03:54 PM
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Joined: Aug 2003
Posts: 43,744 Bend,OR USA
Cab_Burge
I Win
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I Win
Joined: Aug 2003
Posts: 43,744
Bend,OR USA
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I'm glad to hear that your not seeing cap walk Are you running the stock caps in your motor? If not what type did you use, steel, aluminum or ductile iron? Thanks for this information
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: weedburner]
#2455760
02/22/18 07:08 PM
02/22/18 07:08 PM
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Joined: Jan 2008
Posts: 4,269 Canada
WO23Coronet
master
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master
Joined: Jan 2008
Posts: 4,269
Canada
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If your racing where the engine rpm varies very little, like a Powerglide equipped drag car with 800-1000 rpm drop on a single shift, there won't be much advantage to a liteweight crankshaft / rotating assy. If you are racing where the engine rpm varies a lot, like a 4spd manual drag car losing 2000rpm on each of 3 shifts, weight of the rotating assy can make a big difference.
Here's a comparison of two engines that I installed a street/strip manual 4spd car, only significant difference between them was different component weights. Not Mopar, but the results are still relevant...
...Engine #1 was 4.04" x 3.48" w/ 5.7" i-beam rods, hypers with gas ported spacers and 1.2mm rings (12lb oil), 49lb crank and heavy 8" balancer, 1863g bobweight.
...Engine #2 is 4.03" x 3.48" w/ 6" aluminum rods, forged pistons with lateral gas ports and 1.5mm rings (14lb oil), 42lb crank with pendulum style counterweights, drilled rod journals, 6" balancer, 1492g bobweight .
Both had flat tops with nearly identical quench and compression. Exact same intake and carb, same carb calibration. Exact same cam installed on the exact same intake centerline. Exact same flywheel and pressure plate installed in exactly the same car, same weight, with exactly the same gearing and tires. Even though these tests were a couple weeks shy of 2 years apart, both tests are on the same location with zero tire spin and conditions were very close to the same. The car itself was basically a time capsule...I lost engine #1 a few weeks after the test, and i had other irons in the fire so the car sat until engine #2 was ready to install...just picking up where i had left off with regard to developing the car. Here's the average rates that each engine gained rpm WOT thru the gears...
1st gear 2000 to 4000 rpm- engine #1 1634 rpm/sec........engine #2 1910 rpm/sec (276 rpm/sec difference) = 18.8% gain 1st gear 4000 to 6000 rpm- engine #1 1975 rpm/sec........engine #2 2217 rpm/sec (242 rpm/sec difference) = 12.2% gain 2nd gear 4000 to 6000 rpm- engine #1 1070 rpm/sec.......engine #2 1116 rpm/sec (46 rpm/sec difference) = 4.2% gain 3rd gear 4000 to 6000 rpm- engine #1 535 rpm/sec.........engine #2 541 rpm/sec (6 rpm/sec difference) = 1.1% gain No 4th gear data available for comparison.
As you can see, the quicker an engine sweeps thru a gear, the more you will gain from lightweight components. These two engines might both make around 500ft/lbs each running steady state NA, making engine #2's 12.2% gain in 1st gear from 4-6k roughly equal to around a 60hp advantage over engine #1.
Sometimes it helps to think about what happens in opposite extremes...
A given engine has a maximum acceleration rate that it can gain rpm without any external load at all...like a neutral free-rev. At that point all it's power is being used to accelerate itself, and no power is left over to do external work. The lighter an engine's rotating assembly, the easier/quicker it is to accelerate. Sweeping thru the heart of it's torque curve, engine #1 in my example above could gain rpm without a load at the average rate of 8500 rpm per second. Engine #2 could gain rpm without a load at the average rate of 11,515 rpm per second.
On the other end of the spectrum if a car accelerates and works it's way thru the gears, it eventually reaches a point where the engine can no longer accelerate the car. At that point all the engine's power is being used to overcome friction/drag, and there is no power left over for acceleration. This is also the point where the weight of the rotating assy no longer has any effect at all on the power output of the engine. All the torque the engine is making is reaching the transmission's input shaft, no power is being absorbed by the rotating assy as inertia. Operating WOT against maximum load, engine #1 and engine #2 both make the same power.
Looking at these two extremes makes it easier to understand how acceleration rate can have such a huge effect on dyno data. The two otherwise identical engines will make about the same torque when operating against maximum load at a constant rpm, but if engine #1 were dynoed at an acceleration rate of 8500 rpm per second, it would make zero torque on the dyno. Engine #2 still has power left over to move the needle.
If you are running wide open across the ocean, less crankshaft weight will probably hurt you more than help you. If you are a dirt track sprint car on the pole during a re-start, less crankshaft weight is going to be a “BFD”! Most of us here will fall somewhere in between.
Grant So while accelerating, the heavier rotating assembly takes more power to accelerate (makes sense), but would it still not use more power (although considerably less than when getting up to speed) at a static RPM since you are still having to spin a heavier weight? Even at a static velocity, there's always acceleration when dealing with circular motion, is there not?.
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: WO23Coronet]
#2455775
02/22/18 07:36 PM
02/22/18 07:36 PM
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Joined: Oct 2014
Posts: 104 Washington
weedburner
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member
Joined: Oct 2014
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Washington
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So while accelerating, the heavier rotating assembly takes more power to accelerate (makes sense), but would it still not use more power (although considerably less than when getting up to speed) at a static RPM since you are still having to spin a heavier weight? Even at a static velocity, there's always acceleration when dealing with circular motion, is there not?.
Theoretically the entire rotating assy is just an energy storage device, basically one big flywheel. It soaks up energy as it accelerates, then gives that same energy back as it slows down. If that give/take were actually averaging out, there shouldn't be much difference overall in a heavy vs lite crankshaft/flywheel/clutch comparison. But there is a difference that I believe shows up on the time slip for two basic reasons... 1- lower launch rpm compared to the trap rpm. Basically if you were to launch a car at 6000 and trap at 8000, the engine will be burdened with creating enough additional energy during the run to make up that overall 2000rpm difference. Keep in mind the exponential effect that comes with rpm, it takes 16x more energy to accelerate that rotating assy from 6000 to 8000 as it did to accelerate it from 0 to 2000. In this case a lighter rotating assy is an advantage because it will absorb less energy while making up that 2000rpm difference between launch and trap. 2- less energy wasted during a post shift wheelspeed spike. The return of energy after the shift can be so intense that some of the energy released during fallback can be spent in non-productive ways, like knocking the tires loose for an instant. Because a lighter rotating assy releases less energy during fallback, that also reduces the amount of energy wasted as wheelspin after the shift. Grant
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: Al_Alguire]
#2455875
02/22/18 11:16 PM
02/22/18 11:16 PM
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Joined: Nov 2004
Posts: 3,547 Syracuse,NY
CompWedgeEngines
master
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master
Joined: Nov 2004
Posts: 3,547
Syracuse,NY
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Crower can do it as well. Don't have a picture of my Crower crank handy though Al, the Crower price might scare a few of them however.....lol
RIP Monte Smith
Your work is a reflection of yourself, autograph it with quality.
WD for Diamond Pistons,Sidewinder cylinder heads, Wiseco, K1 rods and cranks,BAM lifters, Morel lifters, Molnar Technologies, Harland Sharp, Pro Gear, Cometic, King Engine Bearings and many others.
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: CompWedgeEngines]
#2456052
02/23/18 11:44 AM
02/23/18 11:44 AM
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Joined: Jan 2003
Posts: 9,924 Weddington, N.C.
Streetwize
master
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master
Joined: Jan 2003
Posts: 9,924
Weddington, N.C.
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But also remember it's only one of the rotating components before the power gets to the ground.....so you really need to add in the sum of all the other (assume they are the same as before for comparison) rotating masses (the converter/flywheel, the trans, the driveshaft, the rear axle, the tires and wheels. Yes the mass is less but you really need the sum of the old sums/sum of the new sums and you see the overall percentage of reduced total mass is far lower than you may perceive. Herb Adam's book "Chassis Dynamics" explains this in much more detail....but even though the motor "free Rev's" much easier with a lighter crank.....remember you still have to hook the load to it.
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: Streetwize]
#2456118
02/23/18 02:04 PM
02/23/18 02:04 PM
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Joined: Oct 2014
Posts: 104 Washington
weedburner
member
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member
Joined: Oct 2014
Posts: 104
Washington
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But also remember it's only one of the rotating components before the power gets to the ground.....so you really need to add in the sum of all the other (assume they are the same as before for comparison) rotating masses (the converter/flywheel, the trans, the driveshaft, the rear axle, the tires and wheels.
Yes the mass is less but you really need the sum of the old sums/sum of the new sums and you see the overall percentage of reduced total mass is far lower than you may perceive.
The example in my post on page 3 was basically a direct heavy vs lite crankshaft/pistons/rods comparison, in a real world 4spd manual trans application. The first part did include ALL of the other rotating components. The difference during the 1st gear WOT pull was equal to about a 60hp gain. By 3rd gear, that gain was down to about 5hp. If one were performing that same comparison on an engine dyno, testing at a single acceleration rate would not tell the whole story. Grant
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: CompWedgeEngines]
#2456150
02/23/18 02:37 PM
02/23/18 02:37 PM
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Joined: Jan 2003
Posts: 19,544 Las Vegas
Al_Alguire
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 19,544
Las Vegas
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Crower can do it as well. Don't have a picture of my Crower crank handy though Al, the Crower price might scare a few of them however.....lol Well I'm not gonna say you are wrong for sure They do make a nice product. But it certainly is another level of expense to be sure. But worth the money and less then Bryant or Winberg
"I am not ashamed to confess I am ignorant of what I do not know."
"It's never wrong to do the right thing"
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Re: Anyone use 440 Source Ultralight stroker crank yet?
[Re: Cab_Burge]
#2457891
02/26/18 02:59 PM
02/26/18 02:59 PM
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Joined: Mar 2007
Posts: 3,298 West Coast, USA
jbc426
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master
Joined: Mar 2007
Posts: 3,298
West Coast, USA
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I'm glad to hear that your not seeing cap walk Are you running the stock caps in your motor? If not what type did you use, steel, aluminum or ductile iron? Thanks for this information Thanks for the insight guys. I'm running the stock caps, ARP studs and a Hughes girdle. Interestingly, the engine runs soooo much smoother throughout the RPM range with the new valve train parts and Mike at B3's geometry kit that it is astonishing. I'm thinking that the harmonics that ate up my last valve train is what is missing from this build and likely why the motor feels like it runs so much smoother now. It's a night and day difference.
1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 4.10's 1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3800 stall lock-up converter and 4.30's (closest thing to an automatic 5 speed going)
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